Electric heating and cooking device.



W. S. HADAWAY, JN. ELECTRIC HEATING AND COOKING DEVICE.

APPLICATION FILED MAY 1I 1909. 1,086, 1 6,15,r Patented Feb. 3, 1914.

3 SHEETS-SHEET 1 WITNESSES:

K y NNENIGR BY l,

'ATTORNEY W. S. HADAWAY, JR. ELECTRIC HEATING AND COOKING DEVICE.

APPLICATION FILED MAY lA 1909.

Patented Feb. 3, 1914 3 SHEETS-SHEET 2.

wIINEssEs:

W. S. HADAWAY, Jn. ELECTRIC HEATING AND COOKING DEVICE.

APPLICATION FILED MAY 1, 1909.

Patented Feb. 3, 1914.

3 SHEETS-SHEET 3.

WITNESSES ATTORNEY WILLAM s. HADAWAY, Jn.. or EAST onen ,I ,i l House ELECTRIC AND MANUFACTURING COMPANY,

SYLVANIA.

en, NEW JERSEY, ASSIGNOR To WESTNG- Enncrme HEATING Alim coOmNGD'EvIc-'JL To all whom it may concern' Be it known that `Wnaaan S. Haimway, Jr., a citizen of the United States, and a resident of East Orange, in the county of Essex and State of New Jersey, have invented a new and useful lmprovenient in Electric Heating and Cooking,r Devices, of which the following is a specification.

invention relates to electric heating and cooking apparatus, and it. has special reference to electrically heated ovens.

One. ol'ijeet of lmy invention ie to provide a simple and durahlel heater unit which niay he utilized for various purposes ali-l another object of my invention is to provide an oven or similar deviee wliieh' is adapted to he heated hy a plurality olL the heating units, just referred to, and ivhieh is e'eononiieal in the use of electric energy.

When relatiwly large chaniliers. such as ovens and similar deviees, are heated electrically, an extensive elet-.trie heater is required, and, if this heater is injured iii any way, the whole device is; likely to he ren der-ed inoperative.

According to luy present invention, l provide a large nuinlier of heating' unis .vhieli are interehane'ealle and may reai'lily and Acheaply he replaeed in ease of injury and which may he so electrically connected together in various circuit combinations a: to produce, a greater or less leerer ol' heat when connected diret-,tlY across a eonstaistpotentialircuit. Fach of the units is rigid and durable and is arraned to produce, heat with a n'iiiiimuui e\pen.f'iiturel o' electrienl energy.

Figure 1 of the aeeonipaiiyiug drawings is a plan viewwith the. top removed, Fig. 2 a sectional elevation oi: line Y of Figql and Fig. 3 a Similar rien' on the line BWV-Snif Fig. 2. of an electrically heated oven enihodyine; niy irvention. Figs. 4 and 5 are views, at ripl'it angles to eaeli other, on a larger Fcale,fof one of the heating units shown in Figs. 1, 2 and 3, and Figs. (i, 7, 8 andl9 are detail views of the? 'heading unit of Figs. 4 and 5. y

Referring to Figs. 1, 2 and 8 of the drawings, the devlce here shown comprises a'. hox or oven 1 having a door 2 constituting:A one of the side walls and'hingenconneetecl to the 'body plate 3, and' a plurality of heating specifica-tion of Letters rateiit.

Appncanen fried May 1, 1909. semi No. 493,405'.

units 4 which are removably secured in position within the oven near its top plate. The hex or oven' may be of any suitableconstruction, preferably having an angle iron frame to which sheet metal plates, constitutingI the walls of the device, are attached. Near the top of the oven, a frame 5 is provi.`y` d which is composed of bars 6 and 6al anu cross hars 7, 8 and 9. The bars 6', 6",

7 and 9 are adjacent to the walls of the de4 vire and the bar 8 is se'curetl to the bars G and G substantially midway bctwe'en'the hars 7 and 9. At the haelt of the oven, just ahove ththar 7, a plurality of holes 1() are providedto .receive the electric heating units. Each of the units is in the forni of a flat har and is of such length as to reist upon the cross bars 7, 8 and 9 of the frame 5 when its active part is entirely within the oven. The. terminal end of each unit is en'- larged, as hereinafter described., and the arrangement of parts is Such that thevunit is properly placed when the Aenlarpcnent eonies against the side plates df'the oven.

` Referring to Figs. 4 to 9, inclusive, in |which thel detailed structure of the heater units is illustrated, a resistance Strip or ribhon 1l Ahaving; a series of similar groups of slots cut alternately from opposite edges to provide a zig-zag path for the electrlc eurreiit. (See, Fig. 7), is plaited as shownin Figs. t3 and R to increase the length of the resist- :iure element, a strip 12 of insulation, havingr notches 153 at its ends, heine'l insertedin ear-h plait to Separate the outer surfaces from/the folded-in surfaces. 'l`hc plaited ribbon is not necessarily' slotted in any portion hut the arrangement of the groups of slots, as shown. is such that the folded-in surfaces of the r'ihrlion havea large cin'rei'it-earrying eapaeity` no slots being located in these parts, while the outer surfaces, froi'n whieh the heat may be more readily radiated, are slotted to increase the resistance. This resistanee' elcr'ne'nt is not limited in its iiHe to the-unit illustrated in the other figures-Hut ni'ay be employed for any suitable purpose. nadapt-nr this ty'pe of resistance element, however, to the unit shown in Figs. 4.- and 5, the plaited ribbon is obviously fo'lded haelt on itself in order that hothof the terminals may hebrought ont' at the saine end of the unit.. These terminal ends are also of relavided with a sheath of metal which may be constructed in any suitable way, but is preferably composed of tivo strips of sheet iron` welded together at their edges.

lVhen the heater is to be subjected to very high temperature it may be desirable to employ clear mica for the iusulation'and, when this is used, the notched strips 1Q- serve to center the ribbon within the outer metal jacketor sheath. I

The terminal ends of the casing are separated for a short distance, one of them being offset by making two right angle bends, as shown in Fig. 4, in order to provide a guard for the terminals of the resistance element. This guard is completed by means of a U- shaped punching of sheet iron to which terminal blocks are mechanically secured and from which they are electrically insulated by bolts and insulating bushings.

It may be found of special advantage in some cases'to apply a series of the herein described metal-clad resistance bars to devices of the class illustrated in Patent No. 890,858, granted, June 16, 1908, to the l-ladaway Electric Heating & Engineering Co., comprising metal spacing bars between which the resistance is assembled. ln case of injury, any one of the units could then be re moved and replaced without necessitating the replacement of the entire resistance I do not desire to be limited to the structures illustrated and it will be evident to those skilled in the art that structural modiications lnay be edected within the scope of my invention.

I claim as my invention:

1. An electric resistance element comprising a resistance ribbon folded upon itself at intervals of its length to form an end-to-end series of longitudinally disposed plaits. l

2. A resistance element comprising a resistance ribbon folded upon itself at intervals of its length to form a series of double plaits and insulating' strips fitted into the plaits.

3. An electric resistance element comprising a resistance ribbon folded upon itself at intervals of its length to form a series of double plaits, the folded-in portions being of relatively low resistance and the remaining portions being of rela tively high resistance.

4. An electric resistance element comprising a resistance ribbon folded upon itself at intervals of its length to form a series of plaits, the folded-in portions and the terminal portions being of relatively high current-carrying capacity and the remaining portions being of relatively low current-carrying capacity.

5. An electric resistance device compris'- ing a plaited resistance ribbon and insulating strips fitted into the plaits, said strips being of materially greater Width than the ribbon and having notches at their ends.

6. An electric resistance element comprising insulating strips and a resistance ribbon folded upon said strips at intervals of its length to form an end-to-end series of longitudinally disposed plaits.

7. An electric resistance device comprising-a plaited resistance ribbon, insulating strips fitted into the plaits, and strips of insulation between which the resistance ribbon is assembled, said insulating strips being adapted to be fused together around the resistance strip.

8. A resistance device, comprising a resistance element, a metal sheath composed of strips between which the resistance element is assembled, said strips being secured together at their edges and being offset at one end, and a plurality of terminal members supported by the offset portions of the strips.

9. A resista-nce device comprising a resistance element and a metal sheath composed of strips secured together at their edges, except. at one end, where they are separated to provide a guard for the terminals of the resistance clement.

10. In an electric heating apparatus, the combination with a box or casing having. a plurality of lroles in one wall and interchangeable heating units hav'ing enlarged terminal portions and body portions which ext-end through the holes in the wall of the device.

l1. A heater element comprising a longitudinally extendin electric conductor having a series of paits and an impervious metal sheath insulated therefrom andJcomposed of strips the side .and end edges of which are Welded together to form a homogeneous structure.

12. A heater element comprising an insulated resistance strip Vhaving an end-to-end series of longitudinally disposed plaits and an impervious metal sheath composed of strips the side 4and end edges of which are welded together to form a homogeneous structure.

13. A heater element comprising an insulated conductor, an impervious metal sheath from one end of which said conductor projects and a protecting frame or casing for the, projecting pol-lion m pm'ioim of the conductor.

14. A 11e/nier elementr Cmnpi-ising :m inmilated strip conductor, an impervious miami. sheath Coinpoed of Strips having); theii siii@ and 0nd edgcs welded together :md u terminal-supporting @iid frame or mixing. 

